1. Field
This document relates to a touch display device, and more particularly to a touch integrated display device which can reduce thickness and improve touch performance.
2. Description of the Related Art
Various input devices, such as a keyboard, a mouse, a trackball, a joystick, a digitizer, and the like, are used for an interface between a user and home appliances or various information communication devices. However, in order to use the above input devices, the user should learn how to use the input devices and the quality thereof is not easily improved by causing inconvenience, such as a space necessary for installation thereof. Accordingly, a demand exists for input devices which have convenient and simple functions and can reduce malfunctions. In response, a touch panel has been proposed to enable a user to contact a screen using a hand or a pen to input information.
The touch panel has simple functions, reduces the malfunctions, and enables the user to perform an input without using an additional input device. In addition, the touch panel can be applied to various display devices by enabling the user to perform rapid and easy operations through contents displayed on the screen.
The touch panels can be classified into an add-on type, an on-cell type, and an in-cell type according to structures thereof. The add-on type is a type in which the touch panel is attached on an upper surface of a display device after the display device and the touch panel are separately manufactured. The on-cell type is a type in which elements included in the touch panel are directly formed on a surface of an upper glass substrate of the display device. The in-cell type is a type in which the elements constituting the touch panel are directly formed in the inside of the display device.
However, the add-on type has a structure in which the completed touch panel is mounted on the display device and has the problems, such as increased thickness or reduced visibility due to low brightness of the display device. In addition, the on-cell type touch has a structure in which the touch panel is formed on an upper surface of the display device and can reduce the thickness in comparison with the add-on type but has the problems that the entire thickness is increased by a driving electrode layer, a sensing electrode layer, and an insulation layer for insulating the driving electrode layer and the sensing electrode layer and the increase of the entire thickness and the number of processes causes an increase in manufacturing costs. In addition, the in-cell type can reduce thickness of the display device by forming elements constituting the touch panel in the inside of the display device but has the problem that a driving electrode and a sensing electrode for composing the touch panel cause wirings and parasitic capacitance of the display device and the touch recognition performance is thereby lowered.
Accordingly, a need for display devices rises to solve the problems.